Dihydroprostaglandin e, analogs

ABSTRACT

The invention is a group of prostaglandin analogs of the dihydro-PG1 and PG1 series with the side chains both attached in alpha configuration. These analogs have prostaglandin-like activity but with a different biological potency spectrum than related known prostaglandins.

United States Patent Beal, III et a1.

DIHYDROPROSTAGLANDIN E, ANALOGS Inventors: Philip F. Beal, Ill, Kalamazoo;

Frank H. Lincoln, Jr., Portage; John E. Pike, Kalamazoo, all of Mich.

Assignee: The Upjohn Company, Kalamazoo,

Mich.

Filed: July 16, 1973 Appl. No.: 379,475

Related U.S. Application Data Division of Ser. No. 51,370, June 30. 1970, abandoned, which is a division of Ser. No. 809,046, March 20, 1969, Pat, No. 3,524,867, which is a division of Ser. No. 555,283,.1unc 6, 1966, Pat. No. 3,435,053.

US. Cl....,. 260/468 D'; 260/211 R; 260/247 R; 260/208 R; 260/243.6 S; 260/326.3;

260/410; 260/410.9 R, 260/413; 260/424.9; 260/430; 260/439 R; 260/448 R; 260/488 R; 260/501.1; 260/501.15; 260/501.17; 260/5012; 260/514 D [4 1 July 22, 1975 Int. Cl. C07C 61/38; CO7C 69/74 Field of Search 260/408 D, 514 D, 488 R, 260/410, 410.9 R, 413

References Cited UNITED STATES PATENTS 12/1960 Beal et a1 195/30 Primary Examiner-Robert Gerstl 8 Claims, No Drawings DIHYDROPROSTAGLANDIN E, ANALOGS CROSS REFERENCE TO RELATED APPLICATIONS This application is a division of copending application Ser. No. 51,370, filed June 30, 1970, now aban doned, which is a division of copending application Ser. No. 809,046, filed Mar. 20, 1969, now US. Pat. No. 3,524,867, which is a division of copending application Ser. No. 555,283, filed June 6, 1966, now US. Pat. No. 3,435,053.

This invention relates to compounds related to prostaglandins and having prostaglandin-like activity, and to intermediates used in the manufacture of these compounds. This invention also relates to analogs of prostaglandin E,, and a process and intermediates for their manufacture.

The term prostaglandin is used broadly to designate a material, having hypotensive and smooth musclestimulating activity, obtained from accessory genital glands, seminal fluid, and the like. Prostaglandins have been found to be present in the kidney of both male and female animals. A crude material, designated prostaglandin, was obtained by von Euler from extracts of such materials [Arch. Exp. Path. Pharmak. 175, 78 (1934), 181 (1936), J. Physiol. 72, 74 (1931), 81,102 (1934), 84, 21 (1935), 88, 213 (1936), Klin. Wschr. 14, 118L (1935)]. Recently [Acta Chemica Scandinavia 14, 1693-1704 (1960)] two distinct compounds designated PGE (now known as PGE and PGF (now known as PGF,) have been isolated from crude materials such as von Euler's prostaglandin, and their structures have been determined. The structure of PGE, is:

the plane of the cyclopentane nucleus. PGF

and it is named systematically (using the numbering shown) as 7-[3a-hydroxy-5-oxo-2B-(3-hydroxy-loctenyl)-1 a-yllheptanoic acid. The dotted line attachments shown in the above formula indicate that these substituents are in the (Jr-configuration, i.e., are below is the same as POE, except that the S-oxo group is replaced by an a-hydroxy group.

The side chain double bond in PGE, can be selectively reduced to give dihydro PGE which also exhibits prostaglandin-like activity. Similarly, PGF, gives the active compound dihydro PGF, Other chemical alterations, for example introduction of double bonds at other positions in the side chains, or in the nucleus, lead to prostaglandins having a prostaglandin-like activity, but often profoundly altered in the relative intensity of the effects in the spectrum of prostaglandin activity. The prostaglandins having a keto group at the 5- position of the nucleus are known as the PGE series; those having a S-hydroxy group in place of the keto group are known as the PGF series.

We have discovered that prostaglandin F analogs having cis-side chains (B, B), and a keto group in place of the 3-hydroxy group in the side chain (compounds 1A and 1B in the flow sheet below) lose water and cyclize with unexpected ease, forming dihydropyran derivatives (compounds "A and "B in the flow sheet below) with a a-hydroxy group remaining. The dihydropyran ring was found to hydrolyze very easily in the presence of an acid, giving back the starting material. Oxidation of the hydroxy group in the dihydropyran derivatives, followed by hydrolysis, gives a convenient and valuable process for obtaining prostaglandin E anaiogs from the prostaglandin F analogs already available, without contamination resulting from oxidation of the hydroxyl group at position 3 on the prostaglandin nucleus.

The novel compounds of this invention and the novel processes and intermediates used in their production -are illustratively represented in the following reaction .scheme:

Vl A, V18 1 o l l VIC A-CH-R Vl D wherein R is an alkyl group, either straight or branched 60 or a pharmacologically acceptable cation, A is the ethchain, containing from I to 8 carbon atoms, inclusive, R' is hydrogen or an alkyl group, either straight or branched chain, containing from l to 7 carbon atoms, inclusive, X is hydrogen or methyl with the proviso that not more than one X can be methyl in a given side chain, Y, Y and Y" are hydrogen or carboxyacyl, Z is hydrogen, a hydrocarbyl group containing from I to 12 carbon atoms, inclusive, Z is hydrogen, a hydrocarbyl group containing from 1 to l2 carbon atoms, inclusive,

ylene radical, -CH -CH or the vinylene radical, CH=CH-, and n is 0, l, or 2.

Examples of alkyl, with one to 8 carbon atoms, are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and isomeric forms thereof.

Preferably the carboxyacyl moiety contains one to about l2 carbon atoms. Among the carboxyacyl moieties, lower alkanoyl is preferred.

Examples of lower alkanoyl, i,e., with one to about l2 carbon atoms, are formyl, acetyl, propionyl, butyryl, valeryl, hexanoyl, heptanoyl, octanoyl, decanoyl, undecanoyl, lauroyl, and isomeric forms thereof. Examples of other carboxyacyl moieties within the scope of this invention are crotonyl, cyclohexanecarbonyl, 3- cyclohexenecarbonyl, phenylacetyl, p-chlorophenoxyacetyl, succinyl, benzoyl, p-nitrobenzoyl, naphthoyl, furoyl, 3-pyridinecarbonyl, phthaloyl, and the like.

Preferably the hydrocarbyl moiety contains one to about l2 carbon atoms. Among the hydrocarbyl moieties, alkyl is especially preferred. Examples of alkyl, i.e., with one to about 12 carbon atoms, are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, lauryl, and isomeric forms thereof. Examples of other hydrocarbyl moieties within the scope of this invention are allyl, crotyl, 3-butenyl, hexenyl, propargyl, 4-pentynyl, cyclopentyl, 4-tertbutylcyclohexyl, cyclooctyl, benzyl, Z-naphthylmethyl, and the like.

Pharmacologically acceptable cations within the scope of Z in formulas IV A-D, V A-D, VI A-D, VII, IIIE, and "ID, can be the cationic form of a metal, ammonia, or an amine, or can be quaternary ammonium ions. Especially preferred metal cations are those derived from the alkali metals, e.g., lithium, sodium, and potassium, and from the alkaline earth metals, e.g., magnesium, calcium, strontium, and barium, although the cationic form of other metals, e.g., aluminum, zinc, iron, and silver is within the scope of this invention. Pharmacologically acceptable amine cations can be derived from primary, secondary, or tertiary amines. Examples of suitable amines are methylamine, dimethylamine, trimethylamine, ethylamine, dibutylamine, triisopropylamine, N-methylhexylamine, decylamine, allylamine, crotylamine, cyclopentylamine, dicyclohexylamine, benzylamine, dibenzylamine, a-phenylethylamine, ,B-phenylethylamine, ethylenediamine, diethylenetriamine, and the like lower-aliphatic, lowercycloaliphatic, and lower-araliphatic amines containing up to and including about 18 carbon atoms, as well as heterocyclic amines such as piperidine, morpholine, pyrrolidine, piperazine, and lower-alkyl derivatives thereof, such as l-methylpipe ridine, 4- ethylmorpholine, l-isopropyl-pyrrolidine, 2- methylpyrrolidine, 1,4-dimethylpiperazine, 2-

methylpiperidine, and the like, as well as amines containing water-solubilizing or hydrophilic groups such as mono, di-, and triethanolamine, ethyldiethanolamine, N-butylethanolamine, Z-amino-l-butanol, 2-amino-2- ethyl-1,3-propanediol, 2-amino-2-methyll -propanol, tris(hydroxymethyl)aminomethane, N- phenylethanolamine, N-(p-tert-amylphenyl)diethanolamine, galactamine, N-methylglucamine, N- methylglucosamine, ephedrine, phenylephrine, epinephrine, procaine, and the like. Examples of suitable pharmacologically acceptable quaternary ammonium cations are tetramethylammonium, tetraethylammonium, benzyltrimethylammonium, phenyltriethylammonium, and the like.

In the process of this invention all the compounds can be produced as racemic mixtures. Alternatively, the racemic mixtures can be resolved at appropriate stages by methods well known in the art, whereupon subsequent products may be obtained as the corresponding optically pure enantiomers. In the chart both enantiomeric forms as well as the racemic forms are depicted by a single representation which should, however, not be considered to limit the scope of the disclosure.

The natural prostaglandins exhibit a multitude of pharmacological activities (see for example S. Bergstrom and B. Samuelsson, Ann. Rev. of Biochem., 34, 1965). The prostaglandin analogs of the present invention, compounds IVA-D, VA-D and VIA-D, which possess cis-side chains in contrast to the transside chains of the natural prostaglandins, show a different spectrum of activity as compared to the natural prostaglandins. They act as antagonists of particular activities of the prostaglandins and show a separation of activity between desired and associated activities of prostaglandins.

Compounds IIIA, IVA and IVB possess activity as antagonists to epinephrine in lipid mobilization and are essentially inactive in their action on smooth muscle and in lowering blood pressure. The compounds of formulas IIIA, IVA, and [VB are therefore of value in treating disease states in man where an agent is required that blocks mobilization of free fatty acids (see for example Carlson and Bailey, Chapter 57, Section 5, Adipose Tissue, in Am. Physiological Society Handbook of Physiology).

Compounds IVC, VA-D and VIA-D exhibit hypotensive and smooth muscle stimulating activity. The hypotensive activity of these compounds makes them useful in the control of hypertension in man and valuable domestic animals and in laboratory animals such as mice, rats, and rabbits.

The compounds of formulas IVA-D, VA-D and VIA-D also possess activity as fertility controlling agents, central nervous system regulatory agents, saltand water-retention regulatory agents, fat metabolic regulatory agents and as serum cholesterol-lowering agents which latter activity makes said compounds useful in the prevention of the onset of atherosclerosis and also in the treatment thereof in man and valuable domestic animals. The activity of said compounds as fat metabolic regulatory agents makes them useful in the control of obesity in man and valuable domestic animals. These compounds may be administered to man by intravenous infusion, subcutaneous injection, or by oral and buccal administration.

Compounds IVC, VA-D, and VIA-D produce pronounced changes in blood pressure and block the action of vasopressin on the bladder, altering fluid transport. Agents which counteract or block the actions of prostaglandin are of great interest in clinical research. To assay large numbers of compounds for prostaglandin blocking activity requires a steady supply both for treatment of control animals and for coadministration to test animals with potential blockers. Thus, the compounds listed above can be substituted for PSI-3,, a costly and rare material, in laboratory studies for detecting agents which counteract or block the action of PGE,. The compounds listed above are also useful because they can be administered to laboratory animals, preferably rats, to produce a pharmacologic response similar to that produced by PGE,. Animals so treated can then serve as test animals in the search for and study of compounds which are antagonists of PC-E and of the administered compounds and which, for that reason, would be useful in blocking or terminating their effects and in blocking endogenously produced prostaglandins. For these purposes, the compounds listed above are advantageously administered to the test animal by continuous intravenous infusion in sterile saline solution, at the rate of about 0.l to about l0, preferably 0.1 to 1.0 micrograms per kilogram of animal weight per minute and the blocking agent under study administered before or during treatment to approximately half the animals. The response is measured in each group and compared to determine the blocking action of the test compound.

In addition, compounds [VA-D, VA-D, and VlA-D have a surprising and unexpected influence on animal cell growth in that they inhibit the usual tendency toward cell differentiation during growth. For example addition of small amounts of the compounds of the formulas listed above to isolated growing segments of chicken skin in a nutrient medium inhibits the formation of feather follicles. Because of that activity, the compounds are useful in experimental medicine, for example in studies of wound healing and of other medical problems involving control of cell differentiation during embryological and subsequent animal growth.

Until recently prostaglandins have been available only in milligram amounts after extraction from semen or seminal vesicle tissue. Recently a biosynthetic procedure has been developed for manufacture or prostaglandins from certain essential fatty acids. This procedure has greatly improved the availability of prostaglandin supplies and has permitted limited screening for prostaglandin-blocking agents. The biosynthetic process is, however, complex, as seminal vesicles from noncastrated rams or bulls are required, essential fatty acids are needed for substrate, and a mixture of products is often encountered, purification of which is difficult and tedious. The cost of producing prostaglandins by this method in sufficient amount to satisfy current needs is so high as to be a limiting factor in research. Thus, in addition to the purposes of this invention stated above, e.g., the control of hypertension, fertility control, fat metabolism regulation, etc., by compounds lVA-D, VA-D and VIA-D it is also a purpose of this invention to provide prostaglandins and prostaglandinlike materials to substitute for natural prostaglandins in the prostaglandin antagonist assays. It is still another purpose to provide a synthetic method for preparing prostaglandins and prostaglandin-like materials in substantial amount and in good purity to provide standard materials for use in prostaglandin antagonist assays. it is a further purpose to prepare sufficient prostaglandins and prostaglandin-like materials to permit a large scale screening of large numbers of compounds in sufficient numbers of animals to obtain statistically significant biological data in prostaglandin antagonist assays.

The hexahydro-2,5-dioxo-l-indanealkanoic acids and esters of formula Vll exhibit vasodepressor and lipid mobilizing activity and are useful in the treatment of hypertension and hyperlipemia in man and other animals when administered sublingually, intramuscularly, or intravenously in appropriate dosage forms. An appropriate dosage for ethyl 4-butyl-3a-4,5,6,7,7aahexahydro-2,5-dioxo-lB-indaneheptanoate is from 0.002 to 0.2 'y/kg.

The compounds of formulas "A and "B have prostaglandin-like activity.

In carrying out the process of the present invention, compounds of formula M are cyclized to produce the compounds of formula HA. The cyclization can take place under unexpectedly mild conditions. for example by heating at about C. or above. The reaction can conveniently be carried out in an inert organic solvent. such as toluene, o-, mor p-xylene. n-heptane, noctane, and other hydrocarbon solvents of appropriately high boiling point, about 100 C. or over. Ethers, e.g., dioxane, and like inert solvents can also be used. Water is formed during the reaction, and solvents which form azeotropic mixtures, for example toluene and xylene, are preferred since they provide an efficient means for removing the water.

The time required for reaction depends upon the temperature and the rate at which water is removed. Reaction times of about 1 hour to about 60 hours or longer are operable, about 10 to 50 hours is preferred. To minimize decomposition during the cyclization reaction an inert atmosphere, e.g. nitrogen, is preferred.

If the attached carbon atom in the alkyl group R" of compounds IA and IB carries one or more hydrogen atoms, the cyclized products can have two structures, as shown below for the cyclization of compound IA:

' H l A iii CHE-CH- (cH-cH),,-c0oz H A I x x x I I l CH -CH- (CH-CH) -CO0Z wherein R" is an alkylidene group containing 1 to 8 carbon atoms, inclusive, and R"l-l is the same as R. Varying amounts of "N can be formed depending on the nature of R" and the reaction conditions. Separation of [IA and HA can be accomplished if desired by repeated chromatography over silica gel and by reversed phase partition chromatography on siliconized celite or preparative thin layer chromatography on silica gel. The products can be characterized by mass spectroscopic analysis and nuclear magnetic resonance analysis, and by their characteristic behaviour after ozonolysis. Separation is not necessary for the process of this invention, since the hydroxy group of compounds of formula "N can be oxidized and the oxidized product then hydrolyzed in the same manner to give the same product as described for compounds of structure IIA.

Compounds designated IIB, IIIA', IIIB and IIIC', analogous to HA in having an R group attached by an exocyclic double bond but corresponding otherwise to the compounds of formulas IIB, IIIA, IIIB, and IIIC can likewise be obtained in carrying out the process of this invention. Compounds IIB, IIIA', IIIB and IIIC', either pure or mixed with the corresponding compounds IIB, IIIA, IIIB and IIIC, can be used in carrying out the process of this invention in the same manner as com pounds IIB, IIIA, IIIB and llIC. Formulas IIA, IIB, IllA, IIIB and IIIC in the flowsheet above are intended to represent compounds lIA', IIB, llIA', IIIB and IIIC' as well.

Compounds of formula IIB are prepared by cyclization of the compounds of formula 1B in the same manner as described above for the cyclization of compounds of formula IA. Hydrogenation of the compounds of formula IIB produces compounds of formula IIA. The hydrogenation is carried out under conditions usual for the hydrogenation of ethenoid compounds, and common hydrogenation catalysts can be used; palladium and rhodium are preferred. The hydrogenation is stopped when about the theoretical amount of hydrogen for saturation of the unsaturated carboxylic acid side chain has been absorbed.

The keto compounds of formula IIIA are prepared by oxidation of the hydroxy compounds of formula IIA. Since these compounds are sensitive to acid, acid conditions are preferably avoided during the oxidation reaction. Suitable oxidants are, for example, chromic anhydride in pyridine, dimethylsulfoxide and dicyclohexylcarbodiimide or diisopropylcarbodiimide, and activated manganese dioxide, or the Oppenauer reaction can be used. Isolation of the oxidized product can be accomplished by conventional procedures. During the isolation procedures care must be exercized to avoid acid conditions otherwise some hydrolysis of the pyran ring can take place, giving the prostaglandin analogs of formula IVA. These can be separated if desired from the compounds of formula lllA, by, for example, chromatography over silica gel. For the preparation of compounds of formula IVA, the mixture comprising a compound of formula IIIA and a compound of formula IVA can be used.

The compounds of formula IVA are obtained by acid hydrolysis of the compounds of formula "IA. The hydrolysis is preferably carried out in an aqueous-organic solvent mixture. Methanol, ethanol, acetone, dioxane, dimethylsulfoxide and the like are suitable solvents. Suitable acids include, for example, acetic acid, benzoic acid. succinic acid, lactic acid, chloroacetic acid. p-toluenesulfonic acid, hydrochloric acid, hydrobromic acid and sulfuric acid. The time required for the hydrolysis to reach completion varies from a few minutes to a few hours, depending upon the temperature and the acidity of the hydrolysis mixture. Preferably the hydrolysis is carried out at room temperature or below, with dilute acids, and the reaction mixture is neutralized as soon as substantial hydrolysis has taken place as a precaution against loss of the 3-hydroxyl group, which can occur in substantial amounts in an acid medium. Loss of the hydroxyl group results in formation of compounds of formula VA, which can be separated from the compounds of formula IVA by, for example, chro= mstogrsphy over silica gel.

Isolation of the compounds of formula IVA can be accomplished by conventional methods, for example by neutralizing the acid reaction mixture with a base such as sodium bicarbonate, potassium carbonate, ammonium hydroxide, sodium hydroxide and the like and extracting the product. Purification can be accomplished by conventional methods as described above.

Oxidation of the hydroxyl group of compounds of formula IIB leads to the keto compounds of formula IIIB, wherein the keto group is conjugated with the double bonds in the side chain. This oxidation is carried out in the same manner as the oxidation of compounds of formula IIA to give IIIA. Since the compounds of formula IIB and IIIB are more susceptible to destruction by excess reagent or harsh reaction conditions than compounds of formula [IA and IIIA, careful oxidation under mild conditions is employed. Suitable oxidizing agents are, for example, dicyclohexylcarbodiimide, diisopropylcarbodiimide, together with dimethyl sulfoxide [Moffet et al., JACS 87, 5661 and 5670 (1965)], catalytic oxygenation, the treatment of the chloroformate with dimethyl sulfoxide [Barton procedure, J. Chem. Soc., i855 (i964)] and the Oppenauer process. Preferably the reaction is interrupted as soon as the oxidation is substantially complete. Isolation of the product is by conventional methods well known in the art for working up the oxidation reactions named above.

Compounds of formula VA can be prepared by mixing the compounds of formula IVA with a carboxylic acid and maintaining the mixture until a substantial proportion of the formula IVA reactant is transformed to the desired product. Other acids than carboxylic acids for example, hydrochloric acid, sulfuric acid, and perchloric acid can be used for this transformation of formula IVA compounds to formula VA compounds, but it is usually preferred to use the carboxylic acid because higher yields of relatively pure formula VA compounds are usually obtained thereby.

Although substantially any carboxylic acid can be used as a reagent in the novel process of this invention, it is preferred to use a lower alkanoic acid, i.e., with two to about eight carbon atoms. Examples of lower alkanoic acids are acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, octanoic acid, and isomeric forms thereof, e.g., pivalic acid. Especially preferred as a reactant is acetic acid. Other suitable acids are decanoic acid, crotonic acid, chloroacetic acid, succinic acid, tartaric acid, cyclohexaneacetic acid, maleic acid, adipic acid, benzoic acid, pnitrobenzoic acid, phenylacetic acid, nicotinic acid, and the like.

It is often advantageous, especially with such lower alkanoic acids as acetic acid, to add a small amount of water to the reaction mixture, preferably about one to about 25 percent by weight of the acid reagent. For reasons not completely understood, the water appears to accelerate the reaction and to produce better yields of higher purity product. This is especially true when R, and R, are hydrogen in the formula IVA prostaglandin analog reactant.

The amount of the carboxylic acid reagent is not critical although it is usually advantageous to use at least one molecular equivalent of the acid reagent per molecular equivalent of the formula IVA prostaglsndin analog derivative reactant. It is preferred to use a substantial excess of the carboxylic acid reagent, e.g.,

about to about 5,000 molecular equivalents or even more, per molecular equivalent of the formula IVA reactants, especially when the carboxylic acid reagent is sufficiently volatile to be removed by evaporation or distillation at reduced pressure.

When the carboxylic acid reactant is a liquid at the reaction temperature, excess acid can act as a reaction diluent. An inert diluent can also be added, and use of one is preferred when the acid reactant is a solid at the reaction temperature. Examples of suitable inert diluents are lower alkanols, e.g., ethanol and butanol; lower alkyl lower alkanoates, e.g., ethyl acetate and methyl butyrate; lower alkanones, e.g., acetone and diethyl ketone; dioxane; dialkyl formamides, e.g., dimethyl formamide', dialkyl sulfoxides, e.g., dimethyl sulfoxide; and the like.

The preferred reaction temperature range is about 40 to about 150 C. Especially preferred is the range about 50 to about 100 C. The time necessary to transform a substantial proportion of the formula IVA reactant to the desired formula VA derivative product will depend on such factors as the reaction temperature, the nature and amount of the carboxylic acid reagent, and the nature and amount of the diluent, if one is used. When acetic acid containing percent by weight of water is used with the formula IVA reactant wherein R is pentyl, X and Y are hydrogen, Z is ethyl and it is 2, heating at 60 C. for hours gives satisfactory results.

The formula VA products of the novel process of this invention are usually less polar than the formula IVA reactants. For that reason, a product and the corre sponding reactant can easily be separated by chromatography, preferably by thin layer chromatography.

By that thin layer chromatography, the course of the novel process of this invention can readily be followed by observing the gradual appearance of the desired formula VA product and the gradual appearance of the desired formula VA product and the gradual disappearance of the formula IVA reactant on thin layer chromatograms. Small aliquots of the reaction mixture can be taken during the reaction. When a chromatographic spot corresponding to the formula IVA reactant no longer appears, the reaction is complete.

The desired formula VA product can be isolated from the reaction mixture, if desired, by conventional methods, for example, by evaporation of diluent and excess carboxylic acid, if the latter is sufficiently volatile, or by conventional chromatographic or selective extraction procedures. The formula VA product can also be further purified, if desired, by conventional procedures, preferably by chromatography.

The novel compounds of formula VIA can be prepared by catalytic hydrogenation of the compounds of formula VA. Rhodium and palladium catalysts, espe cially on a carbon carrier, are preferred for this catalytic hydrogenation. It is also preferred that the hydro genation be carried out in the presence of an inert liquid diluent, for example, methanol, ethanol, dioxane, ethyl acetate, and the like. Hydrogenation pressures ranging from about atmospheric to about 50 p.s.i., and hydrogenation temperatures ranging from about 10 to about 100 C. are preferred. The formula VIA product can be isolated by conventional techniques, for example, removal of the catalyst by filtration, followed by evaporation of the solvent. The product can then be purified, advantageously by chromatography. Silica gel and diatomcaeous earth are especially preferred as the chromatography solids.

The compounds of formula IVB are prepared from the compounds of formula IVA by treatment with excess selenium dioxide in an inert solvent, for example tetrahydrofuran, benzene, toluene, dioxane, and the like. The reaction temperature is preferably from 40 C. to C.', usually the reaction is carried out at the boiling point of the solvent employed. The product is isolated by conventional means, for example by removing the insoluble selenium dioxide from the reaction mixture by filtration, centrifugation, or the like, and extracting or evaporating the resulting solution. The formula IVA product can be further purified by chromatography, for example over silica gel or Florisil (synthetic magnesium silicate), by countercurrent extraction, or by other conventional means.

Compounds of formula VIB are produced from compounds of formula VIA by treatment with selenium dioxide as described above.

Reduction of the compounds of formulas IVA, VA, and VIA with 0.25 molecular equivalent of a borohydride or lithium aluminum (tri-tert.-butoxy)hydride transforms the side chain keto group of the formula IVA, VA, or VIA reactant to an hydroxy group giving the corresponding compounds of formulas IVC, VC and VIC, wherein A is --CH -CH Similar reduction of the compounds of formulas IVB, VB and VIB gives the corresponding compounds of formulas IVC, VC, and VIC, wherein A is CH=CH. These reductions can be carried out by methods known in the art for borohydride reductions of other prostanoic acid derivatives. See, for example, Bergstrom et al., Acta Chem. Scand. 16, 969 (1962) and Anggard et al., .1. Biol. Chem. 239, 4101 (1964). Sodium borohydride, potassium borohydride, or lithium aluminum (tri-tertbutoxy)hydride are preferred for these reductions. Lower alkanols, e.g., methanol and ethanol, are preferred as reaction solvents, although other solvents, e.g., dioxane and diethylene glycol dimethyl ether can also be used, especially in combination with the lower alkanol. It is preferred to add a solution or suspension of the reducing agent to the ketone reactant, although the reverse order can also be used. A reaction temperature in the range about 0 to about 50 C. is usually satisfactory. At about 25 C., the desired reaction is usually complete in about 0.5 to 5 hours. The resulting complex compound is then transformed to the desired product in the usual manner by treatment with aqueous acid, advantageously dilute hydrochloric acid.

The desired formula IVC, VC or VIC reduction product can be isolated by conventional techniques, for example, evaporation of the reaction solvent and extraction of the residual aqueous mixture with a waterimmiscible solvent, for example, diethyl ether. Evaporation of the latter solvent then gives the desired prodnot.

These borohydride or lithium aluminum (tri-tertbutoxy)-hydride reductions of the side chain keto group of formula IVA, VA, VIA, IVB, VB and VIB reactants each produce a mixture of an a hydroxy compound and an isomeric (epimeric) B-hydroxy compound. These mixtures ofisomeric hydroxy compounds can be used for the purposes described herein for compounds of formulas IVC, VC and VIC. Alternatively, the isomeric compounds in a pair of hydroxy compounds can be separated from each other by methods known in the art for the separation of analogous pairs of isomeric prostanoic acid derivatives. See, for example, Bergstrom et al., Acta Chem. Scand. I6, 969 (1962), Granstrom et al., J. Biol. Chem. 240, 457 (1965), and Green et al., ibid. Especially preferred as separation methods are partition chromatographic procedures, both normal and reversed phase, thin layer chromatography, and countercurrent distribution pro cedures.

An alternate route for the production of compounds of formula IVC from compounds of formula llA begins with the acylation of the fia-hydroxy group of the formula IIA compound, for example with acetic anhydride and pyridine. The formula IIA acylate is then treated with dilute acid, as described above for the hydrolysis of formula IIIA compounds to produce formula IVA compounds, giving the -monoacylate of a formula I compound, which is treated with sodium borohydride to reduce the side chain keto group. The thus obtained diol is treated with dihydropyran in the presence of an acid to etherify the hydroxy groups, then the S-acyl group is removed by alkaline hydrolysis and the free 5- hydroxy group is transformed to a keto group by oxidation with, for example, chromium trioxide in pyridine giving the di-tetrahydropyranyl ether of the formula IVC compound. The formula IVC compound can then be obtained by removal of the ether protecting groups, for example by treatment with 90% acetic acid.

Reduction of the compounds of formulas IVA, VA, VIA, IVB, VB and VIB as described above but with excess borohydride or lithium aluminum (tri-tert-butoxy) hydride produces the corresponding compounds of formulas IVD, VD and VID, wherein both the side chain and the nuclear keto groups are reduced to hydroxy. Preferably about I to about l5 molecular equivalents of reducing agent is used per molecular equivalent of ketone reactant. The compounds of formulas lVD, VD and VID can be separated and purified as described above for the products IVC, VC and VIC.

Compounds of formulas IVB, lVC, and IVD possess hydroxy or acyloxy groups at position 3 of the cyclopentane nucleus and can be dehydrated in the presence of an acid to give the B-unsaturated compounds of formulas VB, VC, and VD under the conditions described above for the preparation of compounds of formula VA from the compounds of formula IVA. The 3 unsaturated compounds VB, VC and VD can then be hydrogenated to give the compounds of formulas VIB, VIC and VID under the conditions described above for the hydrogenation of the compounds of formula VA to produce the compounds of formula VIA. When the side chain at position 2 is also unsaturated as in VB, VC(A= CH=CH), and VIC (A= CH=CH-)hydrogenation with one equivalent of hydrogen results in a mixture of products. If about two equivalents of hydrogen is used, then only the formula VI products with both ring and side chain saturated are isolated, i.e., compounds of formulas VIA, VIC (A= -CH- ,CH and VID (A= CH CH The compounds of formula llIA, when treated with an acid, give prostaglandin analogs having a cis side chain configuration, i.e., the compounds of formula IVA. Prostaglandin analogs having a trans side chain configuration can be obtained from the compounds of formula IIIB, i.e., the compounds of formula IIID. When compounds of formula IIIB are treated with an acid, as described above for the preparation of compounds of formula IVA from the compounds of for mula IIIA, the ylidene compounds of formula IIIE are obtained and these can be hydrogenated to give the compounds of formula IIID following the procedure used for the reduction of the compounds of formula "B to give the compounds of formula IIA. Alternatively the compounds of formula IIIB can be first hydrogenated to give compounds of formula IIIC, and these on acid treatment as described above give the compounds of formula IIID. The compounds of formula IIID have PGE antagonist activity and anti-lipolytic activity and are therefore useful in treating disease of abnormal lipid transport or metabolism.

The prostaglandin analogs of formulas IVA-D, VA-D, VIA-D, IIID and IIIE, and compound VII can all possess an esterified carboxyl group. Hydrolysis of the ester group is carried out in a conventional manner, preferably with a dilute alkali such as sodium or potassium hydroxide, or sodium or potassium carbonate or bicarbonate, in an aqueous-organic solvent mixture. The product is recovered in a conventional manner, for example, by acidification of the reaction mixture and extraction with a water-immiscible solvent, use of an ion exchange resin etc.

The compounds of formula IVA, when heated with a base such as sodium or potassium hydroxide, sodium or potassium carbonate, and the like in an organic or aqueous organic solvent, for example methanol, ethanol, propanol, butanol, tbutanol, dioxane and the like, preferably at the reflex temperature of the solvent, are transformed to the hexahydro-2,5-dioxo- 1 -indane alkanoic acids of formula VII. The formula VI] product is recovered in a conventional manner, for example, by acidification of the reaction mixture and extraction with a water-immiscible solvent, use of an ion exchange resin, etc. The product is purified in a conventional manner, for example by chromatography over acidwashed silica gel and elution with ethyl acetate, ethyl acetate-benzene mixture, and the like.

The thus obtained free acids of formulas IVA-D, VA-D, VIA-D, IIID, IIIE and VII can be converted to their corresponding esters. This reaction is carried out by reacting the selected acid with a diazoalkane, e.g., diazomethane, diazoethane, diazobutane, l-diazo-Z- ethylhexane, cyclohexyldiazomethane, diazododecane, and the like, in the presence of an inert organic solvent, e.g., methanol, diethyl ether, tetrahydrofuran, dioxane, chloroform, and the like, or a mixture thereof, preferably in a 10% methanol diethyl ether mixture at a temperature of 0 C. to 50 C., with room temperature (25 C.) being preferred. The products are then purified by conventional means, e.g., evaporation to residue, followed by chromatography.

An alternative method for esterification of the free acids of formulas IVA-D, VA-D, VIA-D, IIID, IIIE and VII comprises transformation of the free acid to the corresponding silver salt, followed by interaction of that salt with a hydrocarbyl iodide. Examples of suitable iodides are methyl iodide, ethyl iodide, butyl iodide, isobutyl iodide, tert-butyl iodide, decyl iodide, benzyl iodide, cyclohexyl iodide, crotyl iodide, and the like. The silver salts are prepared by conventional methods, for example, by dissolving the acid in cold dilute aqueous ammonia, evaporating the excess ammonia at reduced pressure, and then adding the stoichiometric amount of silver nitrate.

Carboxyacylation of the hydroxy moiety or moieties in formula A, "B, [VA-D, \AC, VD, VlC, VID, "IE and D prostaglandin analogs is accomplished by interaction of the hydroxy compound with a carboxyacylating agent.

Although substantially any carboxyacylating agent can be used to produce these carboxyacylates, especially suitable are the anhydrides, mixed anhydrides, and acid chlorides of alkanoic, cycloalkanoic, alkenoic, cycloalkenoic, aralkanoic, aromatic, and heterocyclic carboxylic acids. These anhydrides and acid chlorides can also be substituted with any of a wide variety of atomic or molecular moieties. Examples of such substituents are alkyl, e.g., methyl, butyl, decyl; alkoxy, e.g., methoxy, ethoxy, pentyloxy; alkylthio, e.g., methylthio, propylthio, heptylthio; dialkylamino, e.g., dimethylamino, diethylamino, dihexylamino; alkoxycarbonyl, e.g., methoxycarbonyl, propoxycarbonyl, nonoxycarbonyl; carboxyacyl, e.g., acetyl, butyryl; carboxamido, e.g., benzamido, acetamido; nitro; fluoro; cyano; and the like. Chlorine, bromine, and iodine can also be substituents on aromatic portions of the carboxyacylating agents.

Examples of suitable anhydrides are acetic anhydride, propionic anhydride, butyric anhydride, isobutyric anhydride, acrylic anhydride, crotonic anhydride, cyclohexanecarboxylic anhydride, benzoic anhydride, naphthoic anhydride, furoic anhydride, and the like, as well as the corresponding anhydrides substituted with one or more of the above-mentioned substituents. Ex amples of suitable acid chlorides are acetyl chloride, propionyl chloride. butyryl chloride, isobutyryl chloride, decanoyl chloride, acryloyl chloride, crotonoyl chloride, cyclohexanecarbonyl chloride, 3- cyclohexenecarbonyl chloride, phenylacetyl chloride, succinyl chloride, benzoyl chloride, naphthoyl chloride, furoyl chloride, B-pyridinecarbonyl chloride, phthaloyl chloride, and the like, as well as the corresponding acid chlorides substituted with one or more of the above-mentioned substituents.

The carboxyacylation is advantageously carried out by mixing the hydroxy compound and the acid anhydride preferably in the presence of a tertiary amine such as pyridine or triethylamine. A substantial excess of the anhydride should be used, preferably about l to about 10,000 moles of anhydride per mole of the hydroxy compound reactant. The excess anhydride serves as a reaction diluent and solvent. An inert organic diluent, for example, dioxane, can be added. It is preferred to use enough of the tertiary amine to neutralize the carboxylic acid produced by the reaction as well as any free carboxyl groups present in the hydroxy compound reactant.

The carboxyacylation reaction is preferably carried out in the range about 0 to about 60 C. The necessary reaction time will depend on such factors as the reaction temperature and the nature of the anhydride and tertiary amine reactants. With acetic anhydride, pyridine, and a 25 C. reaction temperature, a 12 to 24- hour reaction time should be used.

The carboxyacylated product is isolated from the reaction mixture by conventional methods. For example, the excess anhydride can be decomposed with water, and the resulting mixture acidified and then extracted with a solvent such as diethyl ether. The desired carboxyacylate will usually be extracted by the ether and is recoverable therefrom by evaporation. If desired, the

carboxyacylate can be purified by conventional methods, preferably by chromatography.

The free acids of formulas [VA-D, VA-D, VIA-D, MD, [ME and Vll can be transformed to pharmacologically acceptable salts by neutralization with appropriate amounts of the corresponding inorganic or organic base, examples of which correspond to the cations listed above. These transformations can be carried out by a variety of procedures known in the art to be generally useful for the preparation of inorganic, i.e., metal or ammonium, salts, amine acid addition salts, and quaternary ammonium salts. The choice of procedure will depend in part upon the solubility characteristics of the particular salt to be prepared. 1n the case of the inorganic salts, it is usually suitable to dissolve the acid in water containing the stoichiometric amount of a hydroxide, carbonate, or bicarbonate corresponding to the inorganic salt desired. For example, such use of sodium hydroxide, sodium carbonate, or sodium bicarbonate gives a solution of the sodium salt of the prostaglandin analog derivative. Evaporation of the water or addition of a water-miscible solvent of moderate polarity, for example, a lower alkanol or a lower alkanone gives the solid inorganic salt if that form is desired.

To produce an amine salt, the prostaglandin analog derivative can be dissolved in a suitable solvent of either moderate or low polarity. Examples of the former are ethanol, acetone, and ethyl acetate. Examples of the latter are diethyl ether and benzene. At least a stoichiometric amount of the amine corresponding to the desired cation is then added to that solution. If the resulting salt does not precipitate, it can usually be obtained in solid form by addition of a miscible diluent of low polarity or by evaporation. If the amine is relatively volatile, any excess can easily be removed by evaporation. It is preferred to use stoichiometric amounts of the less volatile amines.

Salts wherein the cation is quaternary ammonium are produced by mixing the prostaglandin analog derivative with the stoichiometric amount of the corresponding quaternary ammonium hydroxide in water solution, followed by evaporation of the water.

The racemic products and intermediates of this invention can be resolved into their optically active components by a number of methods of resolution well known in the art. Those compounds which are free acids or capable of being converted to free acids are treated with an optically active base, e.g., cinchonine, quinine, brucine or dand la-phenylethylamine to produce diastereoisomeric salts which can be separated by crystallization. Alternatively, the acid may be esteritied with an optically active alcohol, e.g., dand 1- menthol, estradiol 3-acetate, and the diastereoisomeric esters then resolved. In addition, the compounds containing free hydroxyl groups can be acylated with the acid chloride or anhydride of an optically active acid, or the free acid in the presence of an esterification catalyst, e.g., d-camphorsulfonic acid, a-bromocamphorsulfonic acid, and dand l-6,6-dinitrodiphenic acid, to give diastereoisomeric esters which are resolvable by crystallization.

Resolution of the racemic prostaglandins and prostaglandin-like compounds of this invention can also be accomplished by reverse phase and adsorption chromatography on an optically active support and adsorbent and by selective transformation of one isomer with a biologically-active prostaglandin transforming system,

transformation applied, and the product formed by the enzymatic transformation.

The starting materials for this invention, the compounds of formulas [A and [8, can be prepared by the processes shown in Preparations l to 34, below, and represented by the following sequence of formulas:

wherein Ac is the acyl radical of a hydrocarbon carboxylic acid containing from I to 12 carbon atoms, inclusive, R is an alkyl group, either straight or branched chain, containing from 1 to 8 carbon atoms, inclusive, Z is hydrogen or an alkyl group containing from 1 to 12 carbon atoms, inclusive, W is hydrogen, an alkyl or substituted alkyl group containing from I to 8 carbon atoms, inclusive, or an aryl or substituted aryl group containing from 6 to 8 carbon atoms, inclusive, Y and Y are hydrogen or the acyl radical of a hydrocarbon carboxylic acid containing from 1 to l2 carbon atoms, inclusive, n is an integer selected from the group consisting of 0, l and 2, and X is hydrogen or methyl with the proviso that not more than one X can be methyl in a given side chain.

In a number of the examples which follow, nuclear magnetic resonance spectroscopy (N.M.R.) has been used along with other instrumental properties, such as infra-red ([.R,) and ultraviolet (U.V.) spectroscopy and mass spectroscopy to characterize and define the products obtained. For discussions of N.M.R. spectroscopy and its application as a definitive measurement and identification of chemical compositions see Bhaca and Williams, Applications of N.M.R. Spectroscopy in Organic Chemistry, Holden Day (I964); L. M. Jackman, Applications of Nuclear Magnetic Resonance Spectroscopy in Organic Chemistry, Pergamon, London (1959); J. D. Roberts, Nuclear Magnetic Resonance, McGraw Hill, NY. (I959); Wilberg and Nest,

I I CHZ-CHZ-C-R x x I X X l qwziwdwemwwol l CH -lIH-(iIH-CHlri-CDOZ The Interpretation of N.M.R. Spectra, Benjamin, N.Y. 1962).

All N.M.R. data were obtained on the Varian N.M.R. instrument, Model A-60 (run at 60 megacycles) and reported in cycles per second (cps) downfield from the standard tetramethylsilane.

The following preparations and examples illustrate the best mode contemplated by the inventors for carrying out their invention.

Preparation 1 3aa,4,7,7aa-tetrahydro-l ,3-indanedione l A solution of 26 g. of 4-cyclopentene-l,3-dione and 0.l g. of pyrogallol in 60 ml. of benzene and L5 ml. of acetic acid was cooled in an ice bath and 40 ml. of liquid butadiene was added. The mixture was sealed in a glass pressure vessel and allowed to stand at room temperature for l2 days. The product precipitated and was removed by filtration to give 33.6 g. of 3aa,4,7,7aatetrahydro-l,3-indanedione having a melting point of l63l65 C. A portion was recrystallized from tetrahydrofuran giving pure 3aa,4,7,7aa-tetrahydro-l,3- indanedione having a melting point of l63165 C., U.V. absorption h 244 mu, e=l5,000, infrared absorption maxima at 3034, 2680, 2520, 2500, 1642, 1582, 1525, 1232, and l cm, and the analysis:

Calcd. for C H O z C, 7l.98; H, 7.5l.

Found: c, 71.51; H, 6.80.

Preparation 2 3aa,4,7,7aa-tetrahydro-l ,3-indanedione (l A mixture of 455 g. of 4-cyclopentene-1,3-dione, 26.2 ml. of glacial acetic acid, 1.75 g. of pyrogallol and 1050 m.. of benzene was placed in an autoclave and cooled to 5 C. or lower, then 700 ml. of liquid butadiene was added. The autoclave and contents was allowed to warm to room temperature while stirring for 2 hours, then was allowed to stand at room temperature for 12 days. The precipitated solid was removed by filtration and dried at 50 C. under diminished pressure to give 472 g. of 3aa,4,7,7aa-tetrahydro-l ,3- indanedione having a melting point of l58-161 C. and a UV. absorption A 244 mp, e 15,150.

Preparation 3 3aa,4,7,7aa-tetrahydro-la,3a-indanediol (3A) and racemic 3aa,4,7 ,7aa-tetrahydrol a,3l3-indanediol (3B) A solution of 10.0 g. of 3aa,4,7,7aa-tetrahydro-l,3- indanedione in 220 ml. of absolute ethanol was heated at reflux under nitrogen while 18.0 g. of sodium in small chunks was added as rapidly as possible without foaming over. The mixture was heated at reflux for a total of 3 hours, then was cooled, diluted with 500 ml. of water and extracted with ethyl acetate. The ethyl acetate extract was concentrated by evaporation under diminished pressure to yield a neutral yellow oil comprising 3aa,4,7,7aa-tetrahydro-la,3a-indanediol and racemic 3aa,4,7,7aa-tetrahydrol a,3B-indanediol. The yellow oil was chromatographed over Florisil (synthetic magnesium silicates) and eluted with increasing proportions of acetone in Skellysolve B (mixed hexanes). The first two product fractions in the 15% acetone in Skellysolve B eluates were combined and gave 0.525 g. of crystals melting at 102l06 C., which on recrystallization from acetoneSkellysolve B mixture gave racemic 3aa,4,7 ,7aa-tetrahydro- 101,3,8- indanediol having a melting point of l06-107 C., infrared absorption maxima (Nujol) at 3300, 3060, 1650, 1215, 1152, 1100 and 1050 cm. and the following analysis:

Calcd. for C l-1, C, 70.10; H, 9.15.

Found: C, 70.34; H, 9.15. Nuclear magnetic resonance analysis showed two CH-O absorption peaks, confirming that the diol melting at l06-107 C. is a trans diol.

The remainder of the 15% acetone in Skellysolve B eluates and the 20% acetone in Skellysolve B eluates were combined and evaporated to give 2.62 g. of crystals comprising 3aa,4,7 ,7aa-tetrahydro- 101,301- indanediol having a melting point of 76-80 C.; on recrystallization from acetone-Skellysolve B an analytical sample was obtained having a melting point of 7983 C., infrared absorption maxima (Nujol) at 3300, 3010, 1650, 1090 and 105 1 cm. and the following analysis:

Calcd. for C l-1 0 C. 70.10; H, 9.15.

Found: C, 70.03; H 9.15. Nuclear magnetic resonance analysis showed the presence of one CH-O absorption peak, confirming that the diol melting at 79-83 C. is a cis diol.

Preparation 4 Racemic 3aa,4,7,7aa-tetrahydro-la-hydroxy-3-indanone (2) and racemic 3aa,4,7,7aa-tetrahydrol B-hydroxy-3-indanone (2) A solution of 5.0 g. of 3aa,4,7,7aa-tetrahydro-l,3- indanedione in 150 ml. of isopropyl alcohol was heated at reflux under nitrogen, then 9.0 g. of sodium in pieces was added as rapidly as possible and the mixture was heated at reflux until the sodium dissolved. The mixture was then cooled, diluted with water, and extracted 3 times with ethyl acetate. The ethyl acetate extracts were combined, washed with water, and evaporated to give 2.34 g. of an oil which was chromatographed over Florisil and eluted with acetone-Skellysolve B. On evaporation of the 10% acetone-Skellysolve B eluate there was obtained 1.546 g. of an 011 comprising racemic 3aa,4,7,7aa-tetrahydro-la-hydroxy-3-indanone and racemic 3aa,4,7,7aa-tetrahydro-1B-hydroxy-T indanone having infrared absorption maxima (CH,Cl at 3700, 3500, and 1735 cm.'. The 1735 cm. absorption indicates the presence of a carbonyl group.

Preparation 5 Racemic 3aa ,4,7,7aa-tetrahydro-la-hydroxy-3-indanone (2) and racemic 3aa,4,7,7aa-tetrahydrol B-hydroxy-3-indanone (2) A solution of 3.0 g. of lithium in 400 ml. of liquid ammonia was prepared and a solution of 5.0 g. of 3aa,4,7,- 7aa-tetrahydro'l,3-indanedione in ml. of absolute ethanol was added dropwise. When about three-fourths of the solution of indanedione in ethanol had been added the blue color of the Li/NH disappeared, and an additional 2 g. of lithium was added, then addition of the indanedione was completed. The mixture was stirred until the blue color disappeared, then the ammonia was evaporated on a steam bath under a stream of air giving a residue which was dissolved by addition of 400 ml. of ethyl acetate and 200 ml. of water and stirring. The ethyl acetate layer was separated and the solvent removed by evaporation to give 5.1 g. of an oil comprising racemic 3aa,4,7 ,7 aa-tetrahydro- 1 ahydroxy-3-indanone and racemic 3aa,4,7,7acztetrahydrolB-hydroxy-Ia-indanone having infrared absorption maxima identical with that shown by the product obtained in Preparation 4.

Preparation 6 3aa,4,7,7aa-tetrahydrola,3a-indanediol (3A) A solution of 5.1 g. of 3aa,4,7,7aa-tetrahydro-lahydroxy-3-indanone (obtained in Prepn. 5) was dissolved in 100 ml. of absolute ether and excess lithium aluminum hydride was added. The thus-obtained mixture was stirred at room temperature for 1.5 hours and ethyl acetate was added to destroy the excess lithium aluminum hydride, then saturated aqueous sodium sulfate was added. The mixture was filtered and the or ganic layer was separated and evaporated to give a residue comprising a mixture of 3aa,4,7,7aa-tetrahydrola,3a-indanediol and racemic 3aa,4,7,7aa-tetrahydro- 1a,3B-indanediol, which on crystallization from a mixture of methylene chloride and Skellysolve B (mixed hexanes) gave 2.05 g. of 3aa, 4,7,7aa-tetrahydro- 10:,3a-inclanediol having a melting point of 8l84 C. The mother liquors from this crystallization are evaporated and the thus-obtained residue is chromatographed following the procedure of Preparation 3 to obtain racemic 3aa,4,7,7aa-tetrahydro-la ,3B- indanediol.

Preparation 7 3aa,4,7,7aa-tetrahydro-la,3a-indanediol (3A) A solution of 4.9 g. of 3aa,4,7,7aa-tetrahydro-lahydroxy-S-indanone in 25 ml. of methanol was added to 400 ml. of liquid ammonia, then 1.5 g. of lithium metal was added rapidly. A blue color developed which disappeared after about minutes, then g. of ammonium chloride was added and the ammonia was evaporated under a current of air while heating on the steam bath, giving a residue which was taken up in a mixture of ethyl acetate and water. The ethyl acetate layer was separated and the water layer was extracted with a second portion of ethyl acetate. The ethyl acetate solutions were combined and evaporated to yield a crystalline residue which on crystallization from a mixture of methylene chloride and Skellysolve B gave 1.65 g. of 3aa,4,7,7aa-tetrahydro-1a,3o:-indanediol having a melting point of 78-80 C. The mother liquors are evaporated to give a residue which is chromatographed following the procedure of Preparation 3 to obtain racemic 3aa,4,7,7aa-tetrahydro-l0:,3B-indanediol.

Preparation 8 3aa,4,7,7aa-tetrahydro-la,3a-indanediol (3A) and racemic 3aa.4,7,7aa-tetrahydro-l a,3B-indanediol A solution of 20.0 g. of lac:,4,7,7aa-tetrahydro-l,3- indanedione in 150 ml. of absolute ethanol was added to a solution of 10.0 g. of lithium wire in 1,000 ml. of liquid ammonia and stirred until the blue color disappeared. The mixture was heated on the steam bath and the ammonia was evaporated under a stream of air leaving a residue. The thus-obtained residue was taken up in 1,000 ml. of ethyl acetate and 500 ml. of water. The ethyl acetate layer was separated and washed twice with 500-m1. portions of water, then the ethyl acetate was removed by evaporation in vacuo under diminished pressure to give a colorless oil. The thus-obtained oil was dissolved in 250 ml. of absolute ether and 5.0 g. of lithium aluminum hydride was added. The mixture was stirred at room temperature for 1.5 hours, then excess lithium aluminum hydride was destroyed by addition first of ethyl acetate and then saturated aqueous sodium sulfate. The organic layer was separated by decantation and filtered. Addition of methylene chloride and Skellysolve B caused precipitation of crystals. The solvent was removed from the entire mixture by evaporation under diminished pressure giving l6.38 g. of a crystalline residue comprising 3aa,4.7,7aoi-tetrahydroiG,3d-il'ldi.-tl1di0i and racemic 3aa,4,7.7aa-tetrahydrola.3B-indanediol.

Preparation 9 Sea .4.7 .7aa-tetrahydrol a,3a-indanediol dibenzoate (4A) and racemic 3aa.4,7,7aa-tetrahydrol a,3B-indanediol dibenzoate (4B) A solution of 7.5 g. of a mixture of 3aa.4.7.7aatetrahydro-1a,3a-indanediol and racemic 3aa.4,7.7aatetrahydro-10:,3fi-indanediol in 100 ml. of pyridine was cooled in an ice bath and 16 ml. of benzoyl chloride was added with stirring. The mixture was allowed to stir about l8 hours while the temperature rose gradually to room temperature. The mixture was then poured into ice and water and neutralized with saturated aqueous sodium bicarbonate. The resulting mixture was extracted with methylene chloride and the methylene chloride extract was separated and washed first with dilute hydrochloric acid then with saturated aqueous sodium bicarbonate. The methylene chloride solution was evaporated to give a residue comprising 3aa,4,7,7- aa-tetrahydro-la,3a-indanediol dibenzoate and racemic 3aa,4,7,7aa-tetrahydro-10:,3B-indanediol dibenzoate which was dissolved in Skellysolve B and chromatographed over Florisil. 0n elution with 1% acetone in Skellysolve B the first three product-containing fractions gave partially crystalline residues. These were triturated with methanol, then recrystallized from methanol to give 1.73 g. of racemic 3aa,4,7,7aa-tetrahydrola,3B-indanediol dibenzoate having a melting point of 8889 C., infrared absorption maxima in Nujol at 1710, 1600, 1585, N15, 1070, 1050, and 710 cm"., and the following analysis:

Calcd. for CggHggOfi C, H, 6.12.

Found: C, 76.17; H, 6.27.

Nuclear magnetic resonance analysis showed that this compound was the trans dibenzoate.

The mother liquors from the above trituration-recrystallization of the trans dibenzoate were combined with the remaining product containing fractions from the above chromatogram and the solvents were removed by evaporation, giving a residue which was chromatographed over Florisil and eluted in 20 fractions with a gradient of 0 to l% acetone in Skellysolve B. Fractions l0-l5 were combined to give 5.9l l g. of residue which on trituration with methanol in a dry-ice bath gave 1.76 g. of racemic 3aa,4,7,7aatetrahydrola,3B-indanediol dibenzoate having a melting point of -86 C. Fractions 16-20 were combined to give 1.76 g. of residue comprising 3aa.4.7.7 aatetrahydro-la.3a-indanediol dibenzoate. Fraction 18 was shown by nuclear magnetic resonance analysis to be pure cis dibenzoate.

Preparation l0 3aa,4,7,7aa-tetrahydro-10:,3aindanediol dibenzoate (4A) and racemic 3aa,4,7,7aa-tetrahydrol 0:,3B-indanediol dibenzoate A solution of 44.4 g. of a mixture of 3aa,4,7.7aatetrahydroindane-la,3a-diol and racemic 3aa,4,7,7aatetrahydroindane-l01,3B-diol in 600 ml. of pyridine was cooled in an ice bath and ml. of benzoyl chloride was added dropwise with stirring. The ice bath was removed and the mixture was stirred at room temperature for 5% hours. The mixture was then diluted with 2,000 ml. of methylene chloride and washed with 1.500 ml. of a mixture of 1 vol. of concentrated hydrochloric acid to 1 volume of water. The aqueous wash was rewashed with about 500 ml. of methylene chloride. The methylene chloride solutions were combined and washed with saturated aqueous sodium bicarbonate and then with water. The thus-obtained methylene chloride soluticn was poured onto a 700 g. Florisil column and eluted with 5.000 ml. of methylene chloride. The methylene chloride eluates were concentrated to a sirupy residue by evaporation under diminished pressure. The above residue was dissolved in 500 ml. of

methanol and filtered through a sintered glass funnel. The mixture was cooled by evaporation under a stream of air and seeded with racemic 3aa,4,7,7aa-tetrahydrola,3B-indanediol dibenzoate. The trans dibenzoate separated by crystallization and was removed by filtration. The filtrate was again cooled under a stream of air and seeded, and the above procedure was repeated until no more crystals were obtained. By this process 49.5 g. of racemic 3aa,4,7,7aa-tetrahydroindane- 10:,3B-diol dibenzoate having a melting point of 78-82 C. was obtained. The methanol was then removed from the filtrate by evaporation under diminished pressure to yield a 64.5 g. sirup comprising 3aoz,4- ,7,7aa-tetrahydroindanel a,3a-diol dibenzoate.

Preparation 1 l Racemic 3aa,6,7 ,7aa-tetrahydrol a,3a-dihydroxy-5(4H indanone dibenzoate (5A) A solution of 7.29 g. of crude 3aa,4,7,7aa-tetrahydro-la,3a-indanedioi dibenzoate (shown by vapor phase chromatography to be 75% la,3a-diol dibenzoate and 25% la,3,6-dioi dibenzoate) in 75 ml. of absolute ether was cooled in an ice bath and 8 ml. of a l.9 molar solution of diborane in tetrahydrofuran was added. The mixture was stirred for an hour and then the excess hydride was decomposed by addition of water. A mixture of 6.4 ml. of concentrated sulfuric acid, 8.0 g. of sodium dichromate and 30 ml. of water was added cautiously and the resulting mixture was stirred for about 18 hours at room temperature. The ether layer was separated and the aqueous layer was extracted with ether and methylene chloride. The ether layer and extracts were combined, washed with saturated aqueous sodium bicarbonate and then with water, and evaporated to give a residue which was chromatographed over Florisil and eluted with 5 and l% acetone in Skellysolve B. The acetone eluates were evaporated to give 0.3] g. of racemic 3aa,6,7,7aatetrahydro-lB,3a-dihydroxy-$(4H)indanone dibenzoate having a melting point of l37-l42 C.

The 10% acetone eiuates of the above chromatogram were combined and evaporated to give 3.164 g. of a residue which on crystallization from ether give 2.05 g. of racemic 3aa,6,7,7aa-tetrahydro-la,3a-dihydroxy- ${4l-i1-indanone dibenzoate having a melting point of l08-l12 C., infrared absorption maxima at 3060, 3050, 1710, 1605, 1505, 1470, i280, i113 and 705 -I.

Preparation 1 2 Racemic 3aa,6,7.7aa-tetrahydrol onSa-dihydroxy-SMH indsnone dibenzoate (5A) A. Racemic 3aa,4.7,7aa-tetrshydro-la-hydroxy-B- indanone (2) A solution of 20 g. of 3aa,4,7.7aa=tetrshydro=l,3= indanedione in l50 ml. of absolute ether was added to a solution of l0 3. of lithium in i,000 ml. of liquid am= monis. The blue colored mixture was stirred until the color disappeared, then the ammonia was evaporated under a stream of air while heating on a steam bath and L000 ml. of ethyl acetate was added, followed by 500 ml. of water. The ethyl acetate layer was separated and washed twice with 500 ml. portions of water. then the ethyl acetate was removed by evaporation leaving a residue comprising racemic 3aa,4,7,7aa-tetrahydrola-hydroxy-S-indanone.

B. 3aa,4,7,7aa-tetrahydro-la,3a-indanediol (3A) and racemic 3am, 4,7,7aa-tetrahydro-la,3B-indanediol (3B) The residue of racemic 3aa,4.7,7aa-tetrahydro-lahydroxy-3-indanone (from A, above) was dissolved in 250 ml. of absolute ether and excess lithium aluminum hydride was added with stirring. The resulting mixture was stirred at room temperature for 1.5 hours then the excess hydride was decomposed by adding first ethyl acetate then saturated aqueous sodium sulfate. The mixture was filtered and the ether layer was separated. The ether was removed by evaporation and methylene chloride and Skellysolve B were added, resulting in crystallization of the residue. The solvents were removed by evaporation under diminished pressure to give 16.38 g. of a crystalline residue comprising a mixture of 3aa,4,7,7aa-tetrahydro-la,3a-indanediol and racemic 3aa,4,7,7aa-tetrahydro-la,3/3-indanediol.

C. 3aa,4,7,7aa-tetrahydro-la,3a-indanedioi dibenzoate (4A) and racemic 3aa,4,7,7aa-tetrahydrola,3B-indanediol dibenzoate (4B) A mixture of 30.2 g. of crude 3aa,4,7,7aa-tetrahydro-la,3a-indanedioi and racemic 3aa,4,7,7,aatetrahydro-la,3B-indanediol (prepared in two runs as in B, above) was dissolved in 225 ml. of pyridine and cooled in an ice bath, then 60 ml. of benzoyl chloride was added slowly with stirring. The reaction mixture was then stirred for about 18 hours at room temperature, then was diluted with methylene chloride and washed with water. The methylene chloride layer was separated and the aqueous layer extracted with methylene chloride. The methylene chloride extracts were combined and washed with saturated aqueous sodium bicarbonate, then with dilute ice cold hydrochloric acid and again with aqueous saturated sodium bicarbonate. The methylene chloride was removed by evaporation and the residual syrup was dissolved in methylene chloride and passed over a 200 g. Florisil column. The column was eluted with 2,000 mi. of methylene chloride and the solvent was removed from the eiuate by evaporation under diminished pressure to yield 78 g. of a mixture comprising 3aa.4,7,7aa-tetrahydro-l01,30:- indanediol dibenzoste and racemic 3sa.4,7,7satetrahydrol 0:,3fl-indanediol dibenzoate.

D. Racemic 3aa,6.7.7sa-tetrahydro-la,3a-dihydroxy-5(4i-i)-indanone dibenzoate (5A) and racemic 3 aa,6,7 ,Isa-tetrahydrol B.3a-dihydroxy-5 4H indanone dibenzoate (5B) A solution of 78 g. ota mixture of crude 3aa.4.7.7satetrahydro-laJa-indsnediol dibenzoste snd racemic 3aa,4,7.7aa-tetrahydro-10:,333fl-indanedlol dibensoate (from C, above) in 800 mi. oi absolute ether was cooled in an ice bath, and I00 ml. of a solution of L9 molar dlborane in tetrshydrofursn was added. After 1.5 hours no excess hydride was present. and I further 30 ml. of 1.9 molar diborsne solution was added. The mixture was then stirred for 4 hours at room tsrnpers= ture after which excess hydride was decomposed by the addition of water and an oxidizing mixture of 86 g. of sodium dichromste, ml. of sulfuric acid and 400 ml. of water was added cautiously. The resulting mixture was stirred for about is hours at room temperature and the aqueous layer again extracted with ether. The ether extracts were combined and washed first with water and then with aqueous saturated sodium bicarbonate.

The solvents were removed by evaporation and the residue was mixed with 300 ml. of ether and refrigerated to give 28.03 g. of crystalline product comprising a mixture of racemic 3aa,6.7,7aa-tetrahydro-101,301- dihydroxy- (4H)-indanone dibenzoate and racemic 3aa,6,7,7aa-tetrahydro-1B,3a-dihydroxy-5(4H)- indanone dibenzoate having a melting point of l-l02 C. Nuclear magnetic resonance analysis established that this product was cis la,3a) isomer.

Preparation 13 Racemic 3aa,6,7 ,7aa-tetrahydro- 1 a,3a-dihydroxy-5(4H indanone dibenzoate (5A) A solution of 1 12.5 g. of crude 3aa,4.7,7aa-tetrahydro-laJwindanediol dibenzoate (prepared as in Preparation 10) in l 130 ml. of absolute ether and ml. of tetrahydrofuran was stirred while the reaction system was flushed with nitrogen to remove air. Stirring was continued while diborane was passed in until an ex cess was present, as shown by bubbling when a drop of the reaction mixture was added to 1 ml. of water. Addition of the diborane required about 5 minutes. The reaction mixture was allowed to stand at room tempera ture for about 4.5 hours, then excess diborane was decomposed by dropwise addition of water. The mixture was then cooled in an ice bath and stirred while a mixture of 130 g. of sodium dichromate, 650 ml. of water, and ml. of concentrated sulfuric acid was added cautiously, then stirring was continued at room temperature for about 18 hours. The organic layer was then separated and the aqueous layer was twice extracted with ether and once with methylene chloride. The or ganic layers were combined and washed with water, saturated aqueous sodium bicarbonate, and again with water. The solvent was removed by evaporation under diminished pressure yielding a light yellow syrup which was dissolved in about 400 ml. of absolute ether and refrigerated to allow crystallization. The crystals were separated by filtration to give 46.1 g. of racemic 3aa,6,- 7,7aa-tetrahydrol a,3a-dihydroxy-5(4H )-indanone dibenzoate having a melting point of l00-l09 C.

Preparation 14 Racemic 3aa,4.5 ,6.7,7aa-hexahydro 5a-penty1-101,301,53- indanetriol (6B) An ether solution of n-amyl magnesium bromide was prepared from 30 ml. of l-bromopentane in 200 ml. of ether and 10 g. of magnesium, then ml. of this Grignard solution was added to a solution of l 1.5 g. of rac emic 3aa,6,7,7aa-tetrahydro-1a,3a-dihydroxy- 5(4H)-indanone dibenzoate in 80 ml. of benzene and the mixture was heated for one hour under reflux. Excess Grignard reagent was then decomposed by addition of water. Rochelle salts were added, then ether and tetrahydrofuran and the solid residue was removed by filtration. The solid residue was leached several times with boiling ethyl acetate. The leachings were combined and concentrated by evaporation to give a residue which was crystallized from ethyl acetate to give 3.14 g. of racemic 3aa,4,5,6,7,7aa-hexahydro-5apentyl-la,3a,5B-indanetriol having a melting point of -l67 C. and infrared absorption maxima (Nujol solution) of 3300 and 1077 cm.

Analysis:

30 Calcd for C I-1 0 C. 69.38; H, 10.81.

Found C, 68.77; H, 10.81. Nuclear magnetic resonance analysis showed the structure to be correct.

Preparation 1 5 Racemic 3aa.4,5,6.7,7aa-hexahydro-5a-pentyl-101,301,513- indanetriol (6B) and racemic 3aa,4,5 ,6,7,7aa-hexahydro-5B-pentyl-101,301,501- indanetriol (6B) A solution of n-amyl magnesium bromide was prepared by adding a solution of 273 ml. of bromopentane in 500 m1. of absolute ether to a suspension of 53.5 g. of magnesium turnings in 400 ml. of absolute ether, and 120 ml. of this amyl magnesium bro mide solution (1.88 M) was added dropwise with stirring to a solution of 10.08 g. of 3aa,6,7,7aa-tetrahydrolal3a-dihydroxy-5(4H)-indanone dibenzoate (prepared as in Preparation 13) in 75 ml. of benzene at room temperature. The mixture was then heated under reflux for 2 hours. The excess Grignard reagent was decomposed by addition of water until the inorganic ma terial was a freely stirring white solid. The mixture was then diluted with 250 m1. of Skellysolve B mixed hexanes and the solids were removed by filtration. The solid filter cake was leached with six 250-m1. portions of boiling ethyl acetate and the leachings were combined and evaporated to give 7.23 g. of crystalline residue comprising racemic 3aa,4,5,6,7,7aa-hexahydro- 5a-pentyl-1a,3a,5[3-indanetriol and racemic 3aa,4,5,6 ,7,7aa-hexahydro-5B-pentyl-1a,3a,5a-indanetriol. This residue was leached at room temperature with 250 ml. of Skellysolve B and filtered to give 453 g. of a crystalline mixture of racemic 3aa,4,5,6,7,7,aahexahydroda-pentyl-1a,3a,5B-indanetriol and racemic 3aa,4,5,6,7,7aa-hexahydrodB-pentyb1 a,3a,5o1- indanetriol having a melting point of l62-166 C. Further crystallization affords essentially pure racemic 3aa,4,5,6,7,7aa-hexahydro5oz-pentyl-l01,311,513- indanetriol. If desired, the combined mother liquors from the crystallizations can be chromatographed, e.g., over Florisil, to give additional quantities of the above racemic 3aa,4,5,6,7,7aa-hexahydro-5a-pentylla,3a,5B-indanetriol as well as essentially purified fractions comprising the racemic 3aa,4,5,6,7,7aahexahydro-SB-pentyll l a,3oz,5a-indanetriol.

Following the procedure of Preparations 14 and 15 above, but replacing racemic 3aa,6,7.7aa-tetrahydrola,3o:-dihydroxy-5(4H)-indanone dibenzoate as starting material with other 1,3-diacylates of racemic 32101.6- ,7,7aa-tetrahydro- 1 a,3oz-dihydroxy-5[4H ]-indanone, e.g., the 1,3-diacetate, dipropionate, dibutyrate, dihexanoate, dilaurate, di(phenylacetate), di(phenylpropionate) and the like is productive of racemic 3aa,- 4,5,6,7,7aa-hexahydro-5a-pentyl-1a,3a,5B-indanetriol and racemic 3aa,4,5,6,7,7aa-hexahydro-5B-pentylla,3a,5oz-indanetriol.

Following the procedure of Preparations l4 and 15 above, but substituting other alkyl metal halides or dialkyl cadmium compounds for n-amy1 magnesium bromide is productive of the corresponding racemic 3aoz,4,5,6,7,7aa-hexahydro-5a (and 5B)-alkylla,3a,5l3(and Sod-indanetriol. For example. treating racemic 3aa.6,7,7aa-tetrahydro- 1 01,3 a-dihydroxy- 5(4H)-indanone dibenzoate (or other 1,3-diacy1ate) with methyl magnesium iodide. methyl lithium. diethyl cadmium, propyl cadmium bromide, isopropyl magnesium bromide, butyl magnesium iodide, butyl lithium, 2-butyl magnesium bromide, t-butyl magnesium bromide, Z-amyl magnesium bromide, 3amyl magnesium bromide, hexyl magnesium iodide, Z-hexyl magnesium bromide, heptyl magnesium bromide, octyl magnesium bromidq 2-octyl magnesium bromide, 3-octyl magnesium bromide and phenyl magnesium bromide is productive of racemic 3aoz,4,5,6,7,7aa-hexahydro-5a (and SBl-methyl-laJoaSB (and 5oz)-indanetriol, racemic 3aa,4,5,6,7Jam-hexahydro-Sa (and 5B )-ethylla,3a,5/3 (and Sa )-indanetriol, racemic 3aa,4,5 ,6,7 ,7aa-hexahydro-5o: (and SID-propyll a,3a,5fi (and Sa)-indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and SB)-isopropylla,3a,5B-(and 5a}-indanetriol, racemic 3aa,4,5,6,7,7- aa-hexahydro-5a(and 5B)-butyl-la,3a,5B-(and 5a)- indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and 5B)-(2-butyl)-la,3a,5]3(and 5a)-indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro-5oz(and 5fl)-t-butylla,3a,5B-(and 5a)-indanetriol, racemic 3aa,4,5,6,7- ,Iaoz-hexahydroSa (and SB)-(2-amyl)-1a,3a,SB-(and 5a)-indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro- 5a (and 5B)-(3-amyl)-la,3a,5B-(and 5a)-indanetriol,

racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and 5B)- hexyl- 1 01,3 01,5 B-( and 5a)indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and 5B)-(2-hexyl)- 1a,3a,5B (and Sa)-indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and SB)-heptyl- 101,301,5858 (and 5a)-indanetriol, racemic 3aa,4,5,6,7- ,7aa-hexahydro-5a(and 5B)-octyl-la,3a,5fi(and 5a)- indanetriol, racemic 3aa,4,5,6,7,7aa-hexahydro- 5a(and 5p'3)-(2-octyl) la,3a,5fi(and 5a)-indanetriol, racemic 3aa,4,5,6,7,7ao:-hexahydro-5a(and 5B)-(3- octyl)'la,3a,5B-(and 5a)-indanetriol and racemic 3aa,4,5,6,7,7aa-hexahydro-5a (and SID-phenylla,3a,5f3(and 5oz)-indanetriol.

Preparation 16 la ,3a-p-nitrobenzylidene derivative of racemic 3aa,6,7 ,7aa-tetrahydro-5-amyll a,3a-indanediol (7) A mixture of 0.50 g. of racemic 3aa,4,5,6,7,7aaheXahydrO'Sa-n-amyl-la,3a,5l3-indanetriol, 0.50 g. of p-nitrobenzaldehyde, l0 ml. of benzene, 10 ml. of xylene and 0.10 g. of p-toluenesulfonic acid was heated at reflux under a calcium carbide drying trap for 2.5 hours, thus accomplishing both dehydration and acetal formation, then was cooled and shaken first with aqueous saturated sodium bisulfite then with aqueous saturated sodium bicarbonate. The organic solution was separated and the solvent was removed by evaporation leaving a residue which was dissolved in Skellysolve B and chromatographed over Florisil then eluted with Skellysolve B containing acetone. The 3% acetone in Skellysolve B eluates contained 0.498 g. of the [04,301- p-nitrobenzylidene derivative of racemic 3aa,6,7,7aatetrahydro-S-amyl-la,3a-indanediol which after crystallization from methanol melted at 4953 C. and had infrared absorption maxima (Nujol solution) at 3100, 3000, 1609, [525, 1350, 1087, 1034, 745 and 692 cm. The structure was confirmed by nuclear magnetic resonance analysis.

Preparation 17 la,3a-p-nitrobenzylidene derivative of racemic 3aa,6,7,7aa-tetrahydro-5-amyl-10:,3a-indanediol (7) A mixture of 16.9 g. of mixed racemic 3aa,4,5,6,7- ,7aa-hexahydro-5a-amyl-la,3a,5B-indanetriol and racemic 3aa,4,5,6,7,7aahexahydro-SB-amyl-la,3a,5a-indanetriol (prepared as in Preparation 15), 250 ml. of benzene, 250 ml. of pxylene, 16.9 g. of p-nitrobenzaldehyde and 1.0 g. of p-toluenesulfonic acid was heated at reflux under a Dean Stark water trap and in an atmosphere of nitrogen for 3 hours. This accomplished both dehydration and acetal formation. The mixture was cooled and shaken with saturated aqueous sodium bisulfite, then the solids were removed by filtration and the aqueous and organic layers separated. The organic layer was again washed with saturated aqueous sodium bisulfite, then with saturated aqueous sodium bicarbonate and finally with water. The organic layer was evaporated under reduced pressure and the resulting residue was dissolved in methylene chloride and chromatographed over Florisil. Elution was with 1% acetone in Skellysolve B. The eluates were evaporated and the crystalline residues were recrystallized by dissolving in ether and adding methanol. There was thus obtained a first crop of M02 g. of crystals comprising the 101,30:- nitrobenzylidene derivative of racemic 3aa,6,7,7aatetrahydro-S-amyl-la,3a-indanediol having a melting point of 5456 C. A further 2.4] g. was obtained by removing the solvent from the mother liquors.

Following the procedure of Preparations l6 and 17 but replacing 3aa,4,5,6,7,7aa-hexahydro-5a(and 5B)- amyl-la,3a,5B-(and Sa)-indanetriol with other 3aa,4,5,6,7,7aa-hexahydro-5a(and 5B)-alkylla,3a,5B-(and 5a)-indanetriols, for example those named following Example 18 is productive of the la,3a-p-nitrobenzylidene derivative of the corresponding racemic 3aoz,6,7,7aa-tetrahydro-5-alkyl-101,30:- indanediol.

Following the procedure of Preparations l6 and 17 but replacing p-nitrobenzaldehyde with other aldehydes such as formaldehyde, acetaldehyde, propionaldehyde, chloral, p-bromobenzaldehyde, pchlorobenzaldehyde, p-fluorobenzaldehyde, 2,4,o-trichlorobenzaldehyde and p-carbomethoxybenzaldehyde is productive of the corresponding racemic la,3a-acetal of 3aa,6,7,7aatetrahydro-S-amyl-la,3a-indanediol. Similarly, following the procedure of Examples [9 and 20 but replacing p-nitrobenzaldehyde with other aldehydes such as those mentioned above and replacing racemic 3aa,4,5- ,6,7,7aa-hexahydro-5a(and 5B)-amyl-la,3a,5B(and 5a)-indanetriol with another racemic 3aa,4,5,6,7,7aahexahydro-S a(and 5B)-alkyl- 1 01,3 a,5B(and 5a)-indanetriol, for example, one named following Preparation 15 is productive of the corresponding racemic la,3a-acetal of racemic 3aa,6,7,7aa-tetrahydro-5- alkyl- 1 01,3 a-indanediol.

Preparation 1 8 la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B-amyll (130,401,511- indanetetrol (8 A solution of 0.55 g. of the p-nitrobenzylidene derivative of 3aa,6,7,7aa-tetrahydro-5-amyl-101,30:- indanediol and 0.44 g. of osmium tetroxide in 25 ml. of

absolute ether was stirred at room temperature for about l8 hours, then the mixture was diluted with 25 ml. of tetrahydrofuran and cooled in an ice bath while gaseous hydrogen sulfide was bubbled through for minutes. The solution was then filtered and the solvent was removed from the filtrate by evaporation under diminished pressure giving 0.435 g. of a crystalline residue which was recrystallized from a mixture of ether and Skellysolve B to give 0.106 g. of the la,3a-pnitrobenzylidene derivative of racemic 3aa,4,5,6,7- ,7aa-hexahydro-5B-amyl-la,3a,4a,5a-indanetetrol having a melting point of l67-l70 C. A further crystallization from acetone gave an analytical sample of the la,3a-p-nitrobenzylidene derivative of racemic 3a- 01,4,5,6,7,7aa-hexahydro-5B-amylla,3a,4a,Sa-indanetetrol having a melting point of l70-l75 C. Analysis:

Calc'd for C H O N: C, 64.43; H, 7.47; N, 3.58.

Found: C, 64.10; H, 7.94; N, 3.58.

The structure was confirmed by nuclear magnetic resonance analysis.

Preparation 19 la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B-amyl-la,3a,4a,5aindanetetraol (8) and la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro- Sa-amyl-l a,3a,4B,5B-indanetetraol (8) A solution of l4.02 g. of the la,3a-pnitrobenzylidene derivative of racemic 3aa,6,7,7aatetrahydro-S-amyl-10:,3a-indanediol (prepared as in Preparation 17) in 400 ml. of absolute ether was cooled in an ice bath and 12.3 g. of osmium tetroxide was added with stirring. The mixture was stirred for about l8 hours while the temperature rose gradually to room temperature. Hydrogen sulfide was then bubbled through the mixture for 10 minutes. The mixture was filtered through Celite (diatomaceous earth filter aid) and the solvent was removed from the filtrate by evaporation under diminished pressure leaving 10.75 g. of residue comprising a mixture of the la,3a-pnitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B- am yl- 1 01,3 a,4a,5a-indanetetrol and the la,3a-pnitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-Sa-amyll a,3a,4fl,5B-indanetetrol. This residue was recrystallized from a mixture of acetone and Skellysolve B to give 1.22 g. of crude la,3a-pnitrobenzylidene derivative of racemic 3aa,4,5,6,7- ,7aa-hexahydro-5fi-amyll a,3a,4B,5a-indanetetrol having a melting point of l63l66 C. The mother liquors from this crystallization were chromatographed over Florisil and eluted with Skellysolve B containing l0 to 20% acetone to give 4.66 g. of crystalline product comprising the la,3a-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5a-amylla,3a,4/3,5B-indanetetrol having a melting point of 33-40 C. 0n recrystallization from a mixture of ether and Skellysolve B an analytical sample of the Sa-amyl compound was obtained having a melting point of 4l-44 C.

Preparation 20 1a,.3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B-amyll a,3a,4a,5 aindanetetrol (8) and la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro- Sa-amyl- 1 01,311,435 B-indanetetraol (8) A solution of 1.00 g. of the 10:,3oz-p-nitrobenzylidene derivative of racemic 3aa,6,7,7aa-tetrahydro-5-amylla,3a-indanediol in 50 ml. of tetrahydrofuran was stirred while 25 mg. of osmium tetroxide was added. A solution of 0.60 g. of sodium metaperiodate in 10 ml. of water was then added, followed by 0.60 g. of sodium acetate. The resulting mixture was heated under reflux with constant stirring for 24 hours, then it was concentrated to about a half volume by distillation under reduced pressure. The residual mixture was cooled, diluted with an equal volume of water, and extracted three times with methylene chloride. The methylene chloride extracts were combined, washed with aqueous sodium sulfite, dried over sodium sulfate, and evaporated under reduced pressure to yield a residue which was crystallized from a mixture of acetone and Skellysolve B to give 0.30 g. of the la,3apnitrobenzylidene derivative of racemic 3aa.4,5,6,7,7aa-hexahydro-SB-amyl-la,3a,4a,5a-indanetetrol having a melting point of l55l 62 C. The mother liquors from the above crystallization were concentrated to dryness, dissolved in a minimum volume of a mixture of 30% ethyl acetate and cyclohexane, and placed on a g. column of silica gel. The column was eluted with 25 ml. portions of the same solvent mixture. Fractions 2-4 contained 300 mg. of unreacted starting material. Fractions ll-20 contained 336 mg. of a mixture of the la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B-amyl-la,3a,4a ,Saindanetetrol and the la,3a-p-nitrobenzylidene derivative of racemic 3aor,4,5,6,7,7aa-hexahydro-5a,amylla,3a,4B,5B-indanetetrol.

Following the procedure of Preparations l8, l9 and 20 but substituting for the la,3a-nitrobenzylidene derivative of racemic 3aa,6,7,7aa-tetrahydro-S-amylla,3a-indanediol as starting material other S-alkyl indanediols, e.g., the la,3a-p-nitrobenzylidene derivative of racemic 3aa,6,7,7aa-tetrahydro-5- alkyl-ia,3a-indanediol wherein the alkyl group is methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, t-butyl, Z-amyl, S-amyl, hexyl, 2-hexyl, heptyl, octyl, 2-octyl, 3-octyl, and the like is productive of the corresponding la,3a-p-nitrobenzylidene derivative of racemic 32101.4,- 5,6,7,7aa-hexahydro-5B-alkyllcr,3a,4a,5a-indanetetrol and the la,3a-pnitrobenzylidene derivative of racemic 3aa.4,5,6,7.7aa-hexahydro-Sa-alkyll a,3a,4fi,5fl-indanetetrol.

Following the procedures of Preparation l8, l9 and 20 but substituting for the la,3o:-p-nitrobenzylidene derivative of racemic 3aa,6,7,7aa-tetrahydro-5-alkyl- 10:,3a-indanediol other la,3a-acetals of racemic 3am.- 6,7,7aa-tetrahydro-5-alkyll a,3a-indanediol wherein the acetal group is derived from, for example, formaldehyde, acetaldehyde, propionaldehyde, chloral. pbromobenzaldehyde. p-chlorobenzaldehyde. pfluorohenzaldehyde, 2,4,6-trichlorobenzaldehyde. p-earbomethoxybenzaldehyde and the like is productive of the corresponding la,3or-acetals of racemic 3aa,4,5,6,7,7aa-hexahydro-5B-alkyll a.3a.4a,5a-

indanetetrol and of racemic 3aa.4,5,6.7,7aa-hexahydro-Sa-alkyll a,3a,4B,5B-indanetetrol.

Preparation 2i 3a,5a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-( 3-oxooctyl)cyclopentane-1B- carboxaldehyde (9A) A mixture of0.5 g. of lead tetraacetate and 10 ml. of benzene was added to a mixture of 0.l5 g. of the pnitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-SB-amyll a,3a,4a,5a-indanetetrol in i0 ml. of benzene, then ml. of toluene was added. After stirring at room temperature for one hour, saturated aqueous sodium thiosulfate was added and the organic layer was separated and filtered through Celite (diatomaceous filter aid). The solvent was removed from the filtrate by evaporation under diminished pressure to yield 0.147 g. of a colorless viscous oil comprising the 3a,5a-p-nitrobenzylidene derivative of racemic 301,501- dihydroxy-2B-( 3-oxooctyl)cyclopentane-lB-carboxaldehyde. The structure was confirmed by nuclear magnetic resonance analysis.

Preparation 22 3a,5a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-(3-oxooctyl)cyclopentane-lB- carboxaldehyde (9A) A suspension of 0.5 g. of a mixture comprising the la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aahexahydro-SB-amyl-la,3a,4a,5a-indanetetrol and the la,3a-pnitrobenzylidene derivative of racemic 3aa,4,- 5,6,7,7aa-hexahydro-5 a-amyl-l 01,3 01,48,513- indanetetrol (prepared as in Preparation 19) in 50 ml. of benzene was stirred at room temperature and 1.5 g. of lead tetraacetate was added. Stirring was continued for two hours then l0 m1. of ether and about l0 ml. of water was added. The mixture was filtered through Celite and the organic layer was separated, washed twice with water, and evaporated under diminished pressure to give 0.465 g. of the 3a,5a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-( 3- oxooctyllcyclopentanel B-carboxaldehyde. The structure was confirmed by infrared absorption analysis.

Following the procedure of Preparations 2i and 22 but substituting for the la,3a-p-nitrobenzylidene derivative of racemic 3aa.4,5,6,7,7aa-hexahydro-SB(and 5a)-amyl-la,3a,4a(and 4B), 5a(and 5B)-indanetetrol as starting material the la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5.6,7,7aa-hexahydro-5B(and 5a)alkyl-la,3a,4a(and 4B),5a(and 5fi)-indanetetrol in which the alkyl group is, for example, methyl, ethyl, propyl, isopropyl. butyl, 2-butyl, t-butyl. 2-amyl. 3- amyl, hexyl, Z-hexyl. heptyl, octyl, 2-octyl and 3-octyl is productive of the 3a,5a-p-nitrobenzylidene derivative of the corresponding racemic 3a,5a-dihydroxy-2B- (3-oxoalkyl)cyclopentane-lB-carboxaldehyde, e.g.. the 3a,5a:-p-nitrobenzylidene derivative of racemic 301,50:- dihydroxy-2/3(3-oxobutyl)cyclopentane-1B- carboxaldehyde, racemic 4a,5a-dihydroxy-2B-(3- oxopentyl )cyclopentanelB-carboxaldehyde. racemic 3a,5a -dihydroxy-2fi-(3oxohexyl)cyclopentanelB-carboxaldehyde. racemic 3a,.5a-dihydroxy-2B-(3- oxo-4-methylpentyl )cyclopentanel B-carboxaldehyde, racemic 3a,5a-dihydroxy- 2B-( 3-oxoheptyl )cyclopentanel B-carboxaldehyde, racemic 301,50:- dihydroxy-2B-( 3-oxo-4-methylhexyl)cyclopentanel B- carboxaldehyde, racemic 3a,5a-dihydroxy-2B-(3-oxo- 4 ,4-dimethylpentyl )-cyclopentanel B-carboxaldehyde, racemic 3a,5a-dihydroxy-2/3 (3-oxo-4-methylheptyl)cyclopentane-1/3- carboxaldehyde, racemic 3a,5a-dihydroxy2B-(3-ox0- 4-ethylhexyl)cyclopentanel B-carboxaldehyde, racemic 3a,5a-dihydroxy-2B-(3-oxononyl)cyclopentanelB-carboxaldehyde, racemic 3a,Sa-dihydroxy-2B-(3- oxo-4-methyloctyl )cyclopentanel B-carboxaldehyde, racemic 3a,5a-dihydroxy- 2B-( 3-oxodecyl)cyclopentanel Bcarboxaldehyde, racemic 301,50- dihydroxy-2B-( 3-oxoundecyl )cyclopentanel B- carboxaldehyde, racemic 3a,5a-dihydroxy-2B-(3-oxo- 4-methyldecyl )cyclopentanel Bcarboxaldehyde, and racemic 3a,5a-dihydroxy-2B-(3-oxo-4-ethylnonyl)cyclopentane- 1 B-carboxaldehyde, respectively.

Following the procedure of Preparations 21 and 22 but substituting for the la,3a-p-nitroben2ylidene derivative of racemic 3a,4,5,6,7,7aa-hexahydro-5fi(and 5a)-amyl-la,3a,4a(and 4B),5oz(and 5B)-indanetetrol as starting material other 10:,3a-acetals of racemic 3aa,4,5,6.7,7aa-hexahydro-5B(and 5a)-amylla,3a,4a(and 4B),5oz(and 5B)-indanetetrol wherein the acetal group is derived from, e.g., formaldehyde,

acetaldehyde, propionaldehyde, chloral, pbromobenzaldehyde, p-chlorobenzaidehyde, pfluorobenzaldehyde, 2,4,6-trichlorobenzaldehyde,

p-carbomethoxybenzaldehyde and the like is productive of the corresponding 3a,5a-acetals of racemic 3a,- 5a-dihydroxy-2B-(3-oxooctyl)- cyclopentane- I B-carboxaldehyde.

Following the procedure of Preparations 2i and 22 but substituting for the la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro-5B(and 5a)-amyl-la,3tx,4a(and 4B),5a(and SBHndanetetrol as starting material other la,3a-acetals of racemic 3aa,4,5,6,7,7aa-hexahydro-5fl(and 5a)-alkylla,3a,4a(and 4B),5a(and 5B)-indanetetrol is productive of the corresponding 3a,5a-acetals of racemic 30:,5wdihydroxy-2B-(3- oxoalkyl )cyclopentanel B-carboxaldehyde.

Preparation 23 3a,5a-p-nitrobenzylidene derivative of racemic ethyl trans-[ 3a,5a-dihydroxy-2fl-( 3-oxooctyl)- cyclopent- I fl-yl] acrylate 10A) A mixture of 300 g. of a mixture of the la,3a-pnitrobenzylidene derivative of racemic 3aa.4,5.6,7,7aa-hexahydro-5B- amyll a,3a,4a,5a-indanetetrol and the la,3a-pnitrobenzylidene derivative of racemic 3aa,4,5.6,7,7aa-hexahydro-Sa-amyl-la,3a,4B,5fl-indanetetrol. 250 ml. of benzene and 9.0 g. of lead tetraacetate was stirred for 1 hour at room temperature. The mixture was then diluted with ether and water and filtered through Celite (diatomaceous earth). The filtrate was washed twice with water, and the solvent removed by evaporation at room temperature under reduced pressure to give 2.46 g. oi the 3a,5a-p-nitrobenzylldene derivative of racemic 3a,5a-dihydroxy- 2B-( 3i-oxooetyl icyelopentanel B-carboxaidehyde as an or The thus-obtained aldehyde was dissolved in l50 ml. of methylene chloride and the solution was cooled in an ice bath, then 6.00 g. of carbethoxymethylenetriphenylphosphorane was added the mixture was allowed to warm to room temperature. Stirring was continued for about 70 hours then the solvent was removed by evaporation under diminished pressure and the thusobtained residue comprising the 3a,5a-pnitrobenzylidene derivative of racemic ethyl trans- [3a,5a-dihydroxy-2B-( 3-oxooctyl )-cyclopentl B-yl] acrylate was chromatographed over Florisii. The 8% acetone in Skellysolve B eluates were evaporated to give 2.152 g. of crystalline 3a,5a-p-nitrobenzylidene derivative of racemic ethyl trans-[3a,5a-dihydroxy-2B- (3-oxooctyl)-cyclpent lB-yl] acrylate which after recrystallization from a mixture of ether and Skellysolve B had a melting point of 5860 C., infrared absorption maxima (Nujol solution) at 1710, 1650, 1610, 1520, 1350, 1220, 1180, 1170, 1115, 1080, 1040, 1000, 855, 850 and 755 cm". and the following analysis:

Analysis:

Calcd for C H O N: C, 65.34; H, 7.24; N, 3.05.

Found: C. 65.33; H, 7.30; N, 3.34.

Preparation 24 30:,5a-p-nitrobenzylidene derivative of racemic ethyl trans-[3a,5a-dihydroxy-2B-(3-oxooctyl)-cyclopent lB-yl] acrylate (lOA) A solution of 0.465 g. of the nitrobenzylidene derivative of racemic dihydroxy-2B-(3-oxooctyl)cyclopentanelB-carboxaldehyde (prepared as in Preparation 22) in 25 ml. of methylene chloride was cooled in an ice bath and 0.80 g. of carbethoxymethylenetriphenylphosphorane was added. The mixture was then allowed to stand for about 70 hours at room temperature and the solvent was removed by evaporation under diminished pressure. The thus-obtained residue was dissolved in 50 ml. of a mixture of ethyl acetate in cyclohexane and filtered through 20 g. of silica gel. The silica gel was washed with an additional 200 ml. of 20% ethyl acetate in cyclohexane and the filtrate and washings together were evaporated under diminished pressure to give 0.433 g. ofcrystalline 3a,5a-p-nitrobenzylidene derivative of racemic ethyl tra11s[ 301,5 adihydroxy-2B-(3 oxooctyl)cyclopent-lB-yl] acrylate which after recrystallization from a mixture of acetone and Skellysolve B had a melting point of 56 58 C.

Following the procedures of Preparations 23 and 24, but substituting for the 301,5 a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-(3- oxooctyl)cyclopentane-lB-carboxaldehyde as starting material the 3oz,5a-p-nitrobenzylidene derivative of a 3a,5a-p- 301,50:-

racemic 3a,5a-dihydroxy-2B-(3-oxoalkyl)cyclopentanel B-carboxaldehyde, e.g., the 30:,5a-pnitrobenzylidene derivative of racemic 301,5 a-

Following the procedures of Preparations 23 and 24 but substituting for the 3a,5a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-(3- oxooctyUcyciopentaneJB-carboxaldehyde as starting material other 3a,5a-acetals of racemic 301,50:- dihydroxy-2B-( 3-oxooctyl)cyclopentanel B- carboxaldehyde wherein the acetal group is derived from, for example, formaldehyde, acetaldehyde, propionaldehyde, chloral, p-brornobenzaldehyde, pfluorobenzaldehyde, p-carbomethoxybenzaldehyde, p-chlorobenzaldehyde, 2,4,6-trichlorobenzaidehyde and the like is productive of the corresponding 304,50:-

acetals of racemic ethyl trans- [301,5 a-dihydroxy-2B-( 3-oxooctyl)cyclopentl B-yl] acrylate.

Following the procedures of Preparations 23 and 24 but substituting for the 301,5 a-p-nitrobenzylidene derivative of racemic 3a,5a-dihydroxy-2B-(3- oxooctyl)cyclopentane-lB-carboxaldehyde as starting material other 3a,5a-acetals of racemic 3a,5adihydroxy-2B-(3-oxoalkyl)cyclopentane-113 carboxaldehyde is productive of the corresponding 3a,5oz-acetals of racemic ethyl trans-[3a,5 a-dihydroxy- 2B-(3-oxoalkyl)cyclopent-lB-yl] acrylate.

Substituting carbomethoxyrnethylenetriphenylphosphorane for carbethoxymethylenetriphenylphosphorane in Preparations 23 and 24 is productive ofthe corresponding methyl acrylates.

Preparation 25 3a,5a-p-nitrobenzylidene derivative of racemic methyl 5[3a,5oz-dihydroxy-2B-(3-oxooctyl)cyclopent-lB-yl]-2,4-pentadienoate 10A) A. 3a,5a-p-nitrobenzylidene derivative of racemic 311,50:- dihydroxy-2B-( 3-oxooctyl)cyclopentane-1,8- carboxaldehyde (9A) A suspension of 5.00 g. (0.0l28 mole) of a mixture of the la,3a-p-nitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aahexahydroB-amyl-la,3a,4a,5a-indanetetrol and the la,3oz'pnitrobenzylidene derivative of racemic 3aa,4,5,6,7,7aa-hexahydro- Sa-amyl-la,3a,4B,5B'indanetetrol in 25 ml. of acetic acid was stirred at room temperature and 6.8 g. of lead tetraacetate was added. The mixture was stirred for 5 minutes then 25 ml. of water and 25 ml. of benzene were added and the organic phase separated. The aqueous phase was washed twice more with benzene after which the combined organic layers were washed with water, dried, and evaporated under diminished pressure to give a residue comprising the 30:,5a-pnitrobenzylidene derivative of racemic 301,50! dihydroxy-2B-(3-oxooctyl)cyclopentane-1B- carboxaldehyde.

B. Methylcrotylphosphorane (carbomethoxyallylidenetriphenylphosphorane) A mixture of 5.74 g. (0.032 mole) of methyl 4- bromocrotonate, 8.83 g. of triphenylphosphine and 25 ml. of chloroform was stirred at 0 C. until a clear solution formed. The solution was allowed to stand 5 hrs. at room temperature, then 39 ml. of ice-cold aqueous 5% sodium hydroxide was added and the mixture was shaken for 10 minutes. The organic layer was then separated, washed with water, dried and evaporated under diminished pressure to give a dark orange oil consisting of the phosphorane from triphenylphosphine and 

1. AN OPTICALLY ACTIVE COMPOUND OF THE ABSOLUTE CONFIGURATION OF NATURAL PGE1 OR A RACEMIC COMPOUND OF THE FORMULA:
 2. An optically active compound of the absolute configuration of natural PGE1 or a racemic compound of the formula:
 3. A compound according to claim 1 wherein X, Y, and Y'' are hydrogen, and n is
 2. 4. A compound according to claim 3 wherein R is pentyl.
 5. An optically compound according to claim
 4. 6. A racemic compound according to claim
 4. 7. A compound according to claim 5 wherein Z is hydrogen.
 8. A compound accoRding to claim 6 wherein Z is hydrogen. 